1. Field of the Invention
The present invention relates to an information processing apparatus, an information processing method, a display apparatus and an information processing program. To be more specific, the present invention relates to an information processing apparatus functioning as an OFDM (Orthogonal Frequency Division Multiplexing) receiving apparatus capable of receiving an OFDM signal without increasing the scale of the circuit and without deteriorating the reception quality of demodulation data, relates to an information processing method adopted by the information processing apparatus, relates to a display apparatus for displaying an image based on data generated by the information processing apparatus and relates to an information processing program implementing the information processing method.
2. Description of the Related Art
An OFDM modulation method is adopted in not only ground wave digital broadcasting in Japan, but also a wide range of fields other than the ground wave digital broadcasting. For details of applications of the OFDM modulation method, the reader is suggested to refer to Japanese Patent Laid-open Nos. 2001-345775, 2002-9731, 2004-228853, 2004-336279, 2004-266814, 2004-32030 and 2006-270831 (hereinafter referred to as Patent Documents 1 to 7, respectively).
In accordance with the OFDM modulation method, an OFDM signal is transmitted in OFDM symbol units. In order to provide each of the OFDM symbols with a property of tolerance for multipath transmissions, a rear part of a valid OFDM symbol is attached to a front part of the valid OFDM symbol to serve as a guard interval.
In processing of demodulating a received OFDM signal, a signal detected through an FFT window of a valid OFDM symbol interval is subjected to an FFT (Fast Fourier Transform) process in order to separate the detected signal into those of a plurality of carrier components. In such demodulation processing, if a signal detected through an FFT window of a valid OFDM symbol interval is composed of only signals of the same OFDM symbol including the guard interval thereof, the orthogonality is sustained.